Earlier this year Mosul became a proving ground for the emerging threat of cheap drones used by terror groups. The militants were using the small unmanned aircraft for both attacks and surveillance.

At the peak in February, the Islamic State deployed 10 to 15 drones a day against Iraqi security forces as they fought to clear militants from Mosul, said Air Force Col. John Dorrian, a military spokesman in Baghdad.” – USA Today

ISIS was using commercially available hobby drones and converting them to carry different types of weapons potentially making them lethal. The US military took the ISIS drone threat seriously when it appeared and has effectively neutralized it according to reports from Iraq.

Featured image of a drone in the northern Iraqi city of Mosul carrying two grenades flying in a test flight by Iraqi forces which aim to use it against Islamic State militants by Aris Messinis, AFP/Getty Images